I think these are good signings at the same time. Roma still have defensive problems. Hummels is a very experienced defender. I believe in him. Hermoso is also pretty good. After signing Le Normand, Atletico Madrid wanted to release him.
I don't get it why As Roma chose to sign Hummels at the end of his career and why they are not giving chances to their young talented defenders that can grow up this season by a lot and be an important key players for next seasons .... . Hopefully Lazio will beat As.Roma in all matches from this year and their defenders won't be able to do anything as that would show up how bad this transfers really are.
I remember the early 2000's with Serie A being the home of champions and the best players in the world would have chose to play in Italy but with time passing by , Serie A became the home of retirement of good players from LaLiga , Bundesliga and even Premier League ((.